MAD MAGE SET

maybe i am stupid, maybe not, but i like new mad mage set ( yes i know its not best in slot ) just question, why old stuff like demo set, still best in slot? now its mod 17, why stuff from mod 15 still best ( not all) oky we have realy gud rings, armor( i speak abaut dps) not bad ( i like 10 proc more power) arms ( if you use primal ( mod 15) and ebony, thei stack, ( like more 15% power) boots still best is from mod 15.......and yes srr for my english :DD so why the hell you cant nerf old staff and litle bit buff new stuff ?;D